Reader/Sorter Machines, sometimes called by their nickname “Big Iron” in the banking industry, were large, extremely high-speed devices for scanning and sorting high numbers of documents, most commonly checks. They were usually found in the regional operations centers of larger banks, which collected and processed paper checks from many branches at a time.
Reader/sorters were famous for their enormous size — sometimes measuring 20 feet (6m) in length and weighing half a ton. They were also expensive to own and operate, costing well above $100,000, and requiring special on-site maintenance and dedicated operators due to their size and complexity. Nonetheless, they were among the fastest scanning and sorting devices ever built, with the top models exceeding 2,000 documents per minute rated speed.
While popular from the 1970s through the 1990s, reader/sorter machines began to fall out of favor around the turn of the century, as more check processing was done in branches, rather than operations centers — using smaller, cheaper desktop scanners. Declining volumes of paper checks starting in the 1990s solidified this trend. New production of reader/sorters declined to almost zero toward the end of the first decade in the 2000s. (NCR reportedly sold its final iTran series reader/sorter in 2015, the latest known date any such machine was in new production.) Today, a handful of reader/sorters remain in service, but it is increasingly difficult to find service and obtain the precision-machined parts needed to keep them running.
One of the best-known, and largest, reader/sorter machines was the IBM 3890, introduced in the early 1970s. Many bankers use the nickname “Big Iron” to mean this machine specifically.
Digital Check’s Quantum DS is often referred to as a reader/sorter, and is still in current production. However, it has been reduced to tabletop size, and is therefore somewhat different from the commercial-sized “Big Iron” devices that typically went by that name.